1. Field of the Invention
The present invention relates to a humidity control apparatus, an environment test apparatus, and a temperature and humidity control apparatus.
2. Description of the Related Art
A variety of humidity control apparatuses for controlling the humidity of a predetermined humidity control space are known. Such humidity control apparatuses are provided with a humidifying part for humidifying the air sent to a humidity control space and a dehumidifying part for dehumidifying this air, wherein the humidity of the humidity control space is controlled by controlling the humidification capacity of the humidifying part and the dehumidification capacity of the dehumidifying part. Various configurations are applied as the dehumidifying part of such humidity control apparatuses. For example, the dehumidifier disclosed in JP 2001-136944 or JP 6-304393 can be applied as the dehumidifying part.
Specifically, the dehumidifier disclosed in JP 2001-136944 is a vapor-compression dehumidifier that has an evaporator (cooler) and a condenser and performs dehumidification by evaporating the moisture in the air on the evaporator. The dehumidified air is heated to the temperature close to the room temperature by the condenser and returned to a drying chamber.
In the dehumidifier disclosed in JP 6-304393, a heat absorption part of a peltier element is disposed on the air absorbing side, and a heat release part of the peltier element is disposed on the air emission side. Moist air is cooled by the heat absorption part of the peltier element and builds up dew condensation. Consequently, the air is dehumidified.
The cooling capacity and the dehumidification capacity of the dehumidifier disclosed in Patent Document 1 are great due to its vapor compression configuration, but the problem is that a large amount of power is required to drive this dehumidifier. The sensible heat factor (SHF) of the evaporator is approximately 0.8, and the ratio of a sensible heat load to a latent heat load is large. For this reason, the vapor-compression dehumidifier does not necessarily have a high dehumidifying efficiency but has a great dehumidification capacity.
On the other hand, in the configuration disclosed in JP 6-304393 where the moisture in the air is condensed by cooling the air by means of the heat absorption part of the peltier element, the required power is small, but the problem is that the capacity for cooling the air and the dehumidifying efficiency are low.
Therefore, a problem in applying the dehumidifier of JP 2001-136944 or JP 6-304393, which has a low dehumidifying efficiency, to a dehumidifying part of a humidity control apparatus is that the power for driving the humidity control apparatus increases and the dehumidifying efficiency of the dehumidifying part decreases.